This invention relates to the orthopedic field of vertebroplasty and to the apparatus and process for injecting biological material into the cancellous portion of bones for treatment and support.
Vertebroplasty was introduced to the medical arts as a percutaneous technique for repairing spinal compression fractures by injecting bone cement into the vertebral body. However, the technique quickly expanded to osteoporotic individuals that had been treated with narcotics and immobilization. The bone cement is used to shore up the collapsing vertebrae for support which relieves the pain associated with undue pressure on the nerves.
Radiologists and surgeons are involved in the procedure since the process is monitored by fluoroscopy and has the potential for leakage of the cement into the local blood stream. Some of the critical parameters of the procedure involve the mixing of the cement to an appropriate viscosity, ensuring that the cement is radio-dense for viewing, properly placing the injector inside the cancellous portion of a vertebra, and rigorously controlling injection pressure and quantity. See xe2x80x9cVertebroplasty: Dangerous Learning Curve,xe2x80x9d START-UP, Jun. 2001.
U.S. Pat. No. 6,273,916 to Murphy describes vertebroplasty, generally, as performed on a prepped and draped prone patient who has been injected with a local anaesthetic. A skin incision is made over the selected vertebrae and a needle is inserted in a posterior approach to engage the vertebral body. A suitable cement is prepared using a contrast medium, such as barium powder, mixed with methylmethacrylate powder, and a monomer liquid. The cement (PMMA) becomes unworkable within 4 to 11 minutes from mixing.
Cement is injected into the vertebrae, while visualized by lateral and anterior- posterior X-ray projection fluoroscopy imaging. The injection is halted if the cement starts to extend into unwanted locations, such as the disc space or towards the posterior quarter of the vertebral body where the risk of epidural venous filling and spinal cord compression is greatest. If no unwanted migration is detected, the injection continues until the vertebrae is adequately filled. The amount of cement injected may vary considerably, e.g. from 4 to 36 cc.
Reiley et al, U.S. Pat. No. 6,048,346, teach a posterior-lateral approach for accessing the interior of the vertebrae for injecting bone cement or treatment substances or a combination of both. The bone cement is injected using a caulking gun-like device with a ram rod in the barrel.
Goldenberg et al, U.S. Pat. No. 5,634,473, and Goldenberg, U.S. Pat. No. 5,843,001, both teach a removable handle for biopsy needles used for bone biopsy.
What is needed in the art is a simple apparatus having several components operated by the same handle to perform biopsy and inject high viscosity cement or other biological material or a combination of both in precisely measured quantities.
Accordingly, it is an objective of the instant invention to teach a kit for biopsy and injection of biological materials having a guide needle, cannulas, several different cannula tips, a plunger, a clearing tool, a connector and a universal tool.
It is a further objective of the instant invention to teach a kit for biopsy and injection of biological materials which is sized to deliver a precise amount of biological material.
It is another objective to teach a kit with several interchangeable tips to be fitted on the leading end of the cannula for different penetrations of the bone.
It is yet another objective of the instant invention to teach a procedure for delivery of a biological material at high viscosity and low pressure.
It is a still further objective of the invention to teach a kit for orthopedic use to perform bone biopsy and to deliver a biological material to the cancellous portion of bone.
Other objects and advantages of this invention will become apparent from the following description taken in conjunction with the accompanying drawings wherein are set forth, by way of illustration and example, certain embodiments of this invention. The drawings constitute a part of this specification and include exemplary embodiments of the present invention and illustrate various objects and features thereof.